Report of Investigations 9312: An Improved Method for Preparing Gravimetric Standard Gas Mixtures of Helium-4 in Nitrogen

Details

• Journal Article:
  MISSING
• Personal Author:
  Bibawy, Nabil A. ; Emerson, David E.
• Description:
  An improved method for preparing gravimetric standard gas mixtures of helium-4 in nitrogen has been developed by the U.S. Bureau of Mines. A single-pan 12-kg analytical balance that has a sensitivity of 3 mg is used to prepare the mixture. The balance will accommodate a cylinder having a volume of approximately 4 l that weighs approximately 5 kg. The method has been improved to a precision of +/-0.04 pct by performing four successive dilutions, by improved handling of gases in the manifold, and by using an improved analytical method to select high-purity gases. [Description provided by NIOSH]
• Subjects:
  Gases Helium Mining Nitrogen Occupational Health Safety
• Source:
  MISSING :7 pages
• Series:
  NIOSH Numbered Publications   ; Mining Publications  
• Subseries:
  Report of Investigations
• Document Type:
  Text
• Genre:
  Report
• Place as Subject:
  United States
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HEFO - Helium Field Office
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  12 pdf pages
• NIOSHTIC Number:
  nn:10008167
• Federal Fiscal Year:
  1990
• Peer Reviewed:
  False
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:11f7a1c5f6fe92593913df95cd136424792ce25d0c84607300796ee695f81f1703e8ae5cc8474ffec0c8e3be2d2c7521b4a9d0a9958568a2396652502da00f75
• Download URL:
  https://stacks.cdc.gov/view/cdc/10308/cdc_10308_DS1.pdf
• File Type:
  [PDF - 423.15 KB ]